// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "ui/wm/core/window_util.h"

#include "ui/aura/window.h"
#include "ui/compositor/layer.h"
#include "ui/compositor/layer_tree_owner.h"
#include "ui/wm/core/transient_window_manager.h"
#include "ui/wm/public/activation_client.h"

namespace {

// Invokes RecreateLayer() on all the children of |to_clone|, adding the newly
// cloned children to |parent|.
//
// WARNING: It is assumed that |parent| is ultimately owned by a LayerTreeOwner.
void CloneChildren(ui::Layer* to_clone, ui::Layer* parent)
{
    typedef std::vector<ui::Layer*> Layers;
    // Make a copy of the children since RecreateLayer() mutates it.
    Layers children(to_clone->children());
    for (Layers::const_iterator i = children.begin(); i != children.end(); ++i) {
        ui::LayerOwner* owner = (*i)->owner();
        ui::Layer* old_layer = owner ? owner->RecreateLayer().release() : NULL;
        if (old_layer) {
            parent->Add(old_layer);
            // RecreateLayer() moves the existing children to the new layer. Create a
            // copy of those.
            CloneChildren(owner->layer(), old_layer);
        }
    }
}

} // namespace

namespace wm {

void ActivateWindow(aura::Window* window)
{
    DCHECK(window);
    DCHECK(window->GetRootWindow());
    aura::client::GetActivationClient(window->GetRootWindow())->ActivateWindow(window);
}

void DeactivateWindow(aura::Window* window)
{
    DCHECK(window);
    DCHECK(window->GetRootWindow());
    aura::client::GetActivationClient(window->GetRootWindow())->DeactivateWindow(window);
}

bool IsActiveWindow(aura::Window* window)
{
    DCHECK(window);
    if (!window->GetRootWindow())
        return false;
    aura::client::ActivationClient* client = aura::client::GetActivationClient(window->GetRootWindow());
    return client && client->GetActiveWindow() == window;
}

bool CanActivateWindow(aura::Window* window)
{
    DCHECK(window);
    if (!window->GetRootWindow())
        return false;
    aura::client::ActivationClient* client = aura::client::GetActivationClient(window->GetRootWindow());
    return client && client->CanActivateWindow(window);
}

aura::Window* GetActivatableWindow(aura::Window* window)
{
    aura::client::ActivationClient* client = aura::client::GetActivationClient(window->GetRootWindow());
    return client ? client->GetActivatableWindow(window) : NULL;
}

aura::Window* GetToplevelWindow(aura::Window* window)
{
    aura::client::ActivationClient* client = aura::client::GetActivationClient(window->GetRootWindow());
    return client ? client->GetToplevelWindow(window) : NULL;
}

scoped_ptr<ui::LayerTreeOwner> RecreateLayers(ui::LayerOwner* root)
{
    scoped_ptr<ui::LayerTreeOwner> old_layer(
        new ui::LayerTreeOwner(root->RecreateLayer().release()));
    if (old_layer->root())
        CloneChildren(root->layer(), old_layer->root());
    return old_layer;
}

aura::Window* GetTransientParent(aura::Window* window)
{
    return const_cast<aura::Window*>(GetTransientParent(
        const_cast<const aura::Window*>(window)));
}

const aura::Window* GetTransientParent(const aura::Window* window)
{
    const TransientWindowManager* manager = TransientWindowManager::Get(window);
    return manager ? manager->transient_parent() : NULL;
}

const std::vector<aura::Window*>& GetTransientChildren(
    const aura::Window* window)
{
    const TransientWindowManager* manager = TransientWindowManager::Get(window);
    if (manager)
        return manager->transient_children();

    static std::vector<aura::Window*>* shared = new std::vector<aura::Window*>;
    return *shared;
}

void AddTransientChild(aura::Window* parent, aura::Window* child)
{
    TransientWindowManager::Get(parent)->AddTransientChild(child);
}

void RemoveTransientChild(aura::Window* parent, aura::Window* child)
{
    TransientWindowManager::Get(parent)->RemoveTransientChild(child);
}

bool HasTransientAncestor(const aura::Window* window,
    const aura::Window* ancestor)
{
    const aura::Window* transient_parent = GetTransientParent(window);
    if (transient_parent == ancestor)
        return true;
    return transient_parent ? HasTransientAncestor(transient_parent, ancestor) : false;
}

} // namespace wm
